Construction of Sociobiological Explanations

The central assumptions of sociobiology are embedded in the
explanations sociobiologists propose. To better see how this process is
operationalized, consider the following methodological schema for
constructing sociobiological explanations:

Hypothesize the behavior's adaptive function

First, sociobiologists identify the category of adaptive strategies
relevant to the behavior in general evolutionary theory. For example,
Linda Mealey (1995) reconceptualizes (redescribes) sociopaths in
evolutionarily significant terms as deceptive cheaters. The Prisoner's
Dilemma model applies to the evolution of a society in which the
following conditions are fulfilled: reliable communication mechanisms
exist in which each player can signal that player's intent to behave
one way or another, signals can be honest or deceptive, whether a
behavior maximizes one's interests is contingent on the behavior of the
other players, and rational behavior is behavior that maximizes one's
own interests. In a two-person game, the four possible outcomes are:
Players cooperate, the first player cheats and the second cooperates,
the second cheats and the first cooperates, or both players cheat.
Thus, it is possible for populations to include both honest Cooperators
who do cooperate after signaling cooperation and deceptive Cheaters who
defect after signaling cooperation. (See entry on
prisoner's dilemma.)

Cooperator

Cheater

Cooperator

b/b

d/a

Cheater

a/d

c/c

Table 1. The two-player prisoner's dilemma. The
relative value of the payoffs is a > b >
c > d. In a single round of the game cheating is a
‘dominant’ strategy, meaning that it that maximizes a
player's payoff on any assumption about the strategy of the other
player. See text for discussion.

Identify the type of evolutionary model(s)

Second, sociobiologists identify the conditions under which the
behavior can and cannot evolve by natural selection. Standard
evolutionary game theory shows why populations of social organisms
exhibit stable polymorphisms in which both cooperators and cheaters
exist, rather than one type being uniquely selected and fixed as
universal in the population. Single Interaction Prisoner's Dilemma
models show that the most rational strategy is to defect. Like all
models, the conclusions are dependent on the assumptions, and when more
variables or parameters are added to simple models, these complexities
may change the conclusions. When players interact only once, being a
‘Selfish Cheater’ is an evolutionarily stable strategy
(ESS): a population of Selfish Cheaters could not be invaded by
Cooperators and replaced by Cooperators in evolutionary time.

Iterated Prisoner's Dilemma models show that the most rational
strategy is to cooperate. When players interact frequently, cooperation
is evolutionarily stable because of the role of reputation. Cheaters
get a reputation for cheating and it is in the interest of both
Cheaters and Cooperators to interact with those known to cooperate
rather than those known to cheat. However, Iterated Prisoner's Dilemma
Arms Race models show that neither Cooperation nor Cheating always wins
out. The reputation effect is mediated by the relative ability of the
players to be sensitive to likely cues of honesty and deception or to
hide those cues. The result is an ‘arms-race’ familiar in
predatory-prey interactions, predator-like defectors become more adept
at hiding cues of defection and prey-like cooperators become more
sensitive to subtle cues of deception.

Connect these models to the distinctive attributes of the
behavior

Third, Mealey identifies a defining feature of sociopathy: namely,
the lack of sincere social emotions despite having normal intellectual
abilities. Social emotions motivate behavior. The phenomenological
experience of shame and guilt punishes behavior and negatively
reinforces it, whereas the experience of sympathy and love rewards
behavior and positively reinforces it. Social emotions also communicate
probable intentions to others. The outward expression of emotion, hard
to control by the actor, reliably indicates to others how the actor is
likely to behave in the future. Sociopaths, lacking sincere social
emotions, are adept at giving the outward expression of whatever social
emotion would lead others to cooperate with them in the future.
Sociopaths are predator-like defectors and mimics: others deceived into
cooperating with them become victims or prey.

Postulate one or more life-history strategies

Fourth, sociobiologists consider which developmental strategy those
exhibiting the behavior might adopt that explains trends in the
behavior as it is studied in the non-evolutionary literature. From
Mealey's analysis of the literature, investigators identify both
clinical and sub-clinical levels of sociopathic behavior and its
correlates. From her understanding of evolutionary theory, for
selection to operate there must be discrete types for selection to
select between. The simplest hypothesis is to posit two types of
sociopathic life-histories. ‘Primary sociopaths’ exhibit
clinical levels of antisocial behavior, whereas ‘secondary
sociopaths’ exhibit sub-clinical levels. The behavior of primary
sociopaths is the outcome of genetically based, individual differences
in the use of a single strategy; sociopaths are Cheaters by virtue of
their genotype regardless of the developmental and environmental
variations they experience. In contrast, normal people are Cooperators
by virtue of their genotype regardless of developmental and
environmental variations. The behavior of secondary sociopaths is the
outcome of genetically based individual differences in response to
their environment; normal people and sociopaths respond differently to
environmental stimuli in the course of development and are canalized
(formed or stabilized during a critical period of development) to
produce different sets of limited strategies. Thus, primary and
secondary sociopaths differ genetically from normal people and from
each other. The life-history of secondary sociopaths is more
environmentally-contingent and developmentally-contingent than that of
primary sociopaths.

Gather multi-disciplinary evidence

Fifth, Mealey supports this ‘two-pathway Cheater’ model
of the behavior by showing how it explains variations in the behavior.
Mealey provides evidence from proximate studies that there are
differences in the use of cheating strategies used by sociopaths within
and across environments. These patterns divide into two different
developmental etiologies (causal patterns), which correspond to two
types that natural selection could favor or disfavor in various
conditions.

Identify the biological factors of the trait and its
correlates

Behavioral genetics, using twin and adoptive studies across
cultures, has found evidence that sociopathy has a genetic basis.
Gender and sociopathy are highly associated; in the U.S. sociopaths
comprise 3-4% of the male population and less than 1% of the female
population. This suggests a ‘two-threshold’ polygenic model
in which the genetic component is an outlier (on the extreme of a
normal distribution), polygenic (coded by many genes with interactive
effects) and nearly sex-limited (its genes are expressed only in the
presence of a threshold value of a sex hormone such as androgen and
thus sociopathy is nearly restricted to one sex). Females who express
the trait must be more extreme outliers than males. The two-threshold
model is a better explanation than a ‘sex-linkage
hypothesis’ or a ‘differential experience of the sexes
hypothesis’ of the greater risk for the offspring of female
sociopaths as compared to the offspring of male sociopaths.

Identify sociocultural factors of the trait and its correlates and
establish linkages between biological, psychological, and sociocultural
factors

Social psychological studies show that many people exhibit
antisocial behavior but are not sociopaths, because they express it in
circumstances or ways that are socially approved. Statistical evidence
reveals that a disproportionately large number of people who become
lawyers, entrepreneurs, psychiatrists, or scientists have sociopathic
tendencies. Lawyers can learn to defend a guilty client or prosecute an
innocent one without normal feelings of guilt. Entrepreneurs can learn
to ruthlessly fire staff when their vision of a successful business
changes and the staff do not fit into the new plan. Psychiatrists and
social workers can learn treat their patient's most intimate personal
problems by day and do not care about their patients by night.
Scientists can learn to do experiments on people that cause them
anguish.

The Machiavellianism scale measures this subclinical variation in
antisocial behavior, i.e., levels of self-initiated manipulation and
control of others. Machiavellianism, a high score on the Mach scale, is
defined by agreement with such statements as "Humility is of no service
and is actually harmful," "Nature has so created humans that they
desire everything but are unable to attain it," and "The most important
thing in life is winning." Machiavellianism is best understood as a
low-level manifestation of secondary sociopathy. High Machs, who use an
impersonal, cognitive, rational, cool approach with others, are more
accurate than low Machs in predicting how others answer a Mach
questionnaire, and in competitive situations. Low Machs, who use a
personal, empathy-based, idiographic approach with others, are more
likely to select a Cooperator as a partner, but are vulnerable to being
exploited by others who use the impersonal goal-oriented approach.
These findings are best explained by the two-pathway Cheater model's
claim that secondary sociopaths are at the end of a normal distribution
of genotypes and that selection permits multiple strategies in the
population that are instances of various sorts and degrees of cheating
and cooperation.

Social psychology can go beyond personality and situational
variables that contribute to the development of individual differences
in personality and antisocial behavior, and can tell us how
within-individual factors encourage or discourage cheating. Most
studies show that a positive mood reflects not only past success but
also anticipates future success. Sadness and feelings of failure can
facilitate prosocial behavior in some children and more often in
adults, but if sadness is profound enough to lead to depression, the
subject often opts out of most social interaction, exhibiting asocial
rather than antisocial or prosocial behavior. Secondary sociopaths, who
feel both social emotions (guilt, anxiety, and sympathy) and mood
change (sadness, optimism, anger), are subject to culturally induced
manipulation of both social emotion and mood. Primary sociopaths, who
rarely if ever feel social emotions but experience mood change, are
subject to culturally induced manipulation of mood but not social
emotion.

Some cultures encourage competitiveness more than others.
Competition increases the use of antisocial and Machiavellian
strategies. High population density (e.g., large cities) increases
competition indirectly and is associated with reduced prosocial
behavior and increased antisocial behavior. The two-pathway Cheater
model predicts different relations of primary and secondary sociopathy,
with cultural variation in which the success of sociopaths depends on
their frequency in the population. Primary sociopaths have an inborn
temperament, personality, and pattern of autonomic hypoarousal designed
to make the child selectively unresponsive to cues necessary for normal
socialization and moral development. For this reason, there will always
be a small, cross-culturally similar, and unchanging baseline frequency
of sociopaths. They display chronic, pathologically emotionless
antisocial behavior through most of their lifetime across a variety of
situations, and are equally likely to come from all kinds of
socioeconomic backgrounds.

Because secondary sociopaths differentially use
environmentally-contingent strategies, their frequency can vary across
cultures and environmental conditions. Secondary sociopaths respond to
environmental risk factors with frequent but not necessarily
emotionless cheating, and their strategy choices will be more closely
tied to age, fluctuation in hormone levels, their competitive status
within their group, and changing environmental contingencies. Almost
all upper socioeconomic class sociopaths are primary sociopaths,
whereas secondary sociopaths almost always come from lower class
backgrounds. Life in the upper classes evidently reduces environmental
risk factors. Upward and downward social mobility affects the relative
frequencies of secondary sociopaths, as they respond to different
degrees of risk. Life experiences affecting fitness can move someone in
and out of the secondary sociopath category. These facts—that
primary sociopaths adopt a strategy that is toward the
‘obligate’ or ‘canalized’ end of the
malleability spectrum and secondary sociopaths adopt a strategy toward
the ‘facultative’ or ‘uncanalized’ end of the
malleability spectrum—are important because the degree of
malleability of a behavior is a crucial factor in how we fashion social
policy to deal with it.